Split Ring Compound Planet Epicyclic Gear

Split Ring Compound Planet Epicyclic Gearing is an awesome arrangement of gears that let you have really high gear ratios in just two stages of gearing. This lets you create gearboxes that are powerful, flat, and easy to produce with 3D printing.

There is a newer gear box by the same designer here:
   • Cool Gearing: Sun to Sun Epicyclic Ge...  

Here is a spreadsheet for designing your own:
https://docs.google.com/spreadsheets/...

I also put it and a 'readme' document on github here:
https://github.com/IdeaPropulsionSyst...

These things are great for making solar panel motors, moving telescopes, or for robot arm elbows. Feel free to make use of this for your next DIY engineering project!